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International Comparative Study on Astronomical Exhibits: Focus on Exhibit Characteristics and Earth Science Curriculum Reflected in Exhibits (천체 전시물 비교 연구 -전시특성 및 지구과학 교육과정의 반영 정도를 중심으로-)

  • Kim, Soo Kyung;Park, Eun Ji;Kim, Chan Jong;Choe, Seung Urn
    • Journal of The Korean Association For Science Education
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    • v.36 no.6
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    • pp.925-934
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    • 2016
  • For students, astronomy is not only interesting but also difficult to learn. However, there is a limit in learning astronomy in a school science setting since astronomy is vast subject. Fortunately, science museums can be helpful in overcoming this limitation. Experiences in science museum provide something that any descriptions or illustrations cannot give. Therefore, to maximize the educational effect, it is necessary to look at astronomical exhibits regarding the educational aspects and complement them. For these reasons, the purpose of this study is to investigate characteristics of exhibitions related to astronomy and how much the exhibitions reflect the contents of their science curricula. We selected famous science museums in Korea, America, and Japan and analyzed characteristics of their astronomy exhibition. We analyze these characteristics in the aspects of exhibition technology & media, presentation method and activity types. Also, this study figures out how content of exhibitions are connected to school science curriculum. The results are summarized as follows: First, Science Museums of America and Japan utilize interactive exhibits to raise participation. It implies that Science Museum of Korea needs Interactive Exhibits that provide a realistic experience of the universe. Second, the astronomy exhibits reflect some of the learning elements of their science curricula concerned with astronomy. However, these astronomical contents are included selectively and not according to their required curriculum. It means that many students lack the opportunity to study Astronomy in their schools. Therefore, the astronomy museum must reflect learning elements of science curricula concerned with astronomy in the exhibits.

Age Variation in Extractive Nitrogenous Constituents of the Cultured Ascidian, Halocynthia roretzi Muscle (양식산 우렁쉥이, Halocynthia roretzi 함질소 엑스성분의 연령차)

  • PARK Choon-Kyu
    • Journal of Aquaculture
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    • v.5 no.1
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    • pp.69-79
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    • 1992
  • The muscle extracts of the ascidian, Halocynthia roretzi cultured for two and three years old on the southern coast near Chungmu and the eastern coast near Pohang of Korea, were analyzed for extractive nitrogen (EN), free amino acids (FAA), combined amino acids (CAA), nucleotides and related compounds (NRC), quaternary ammonium bases and guanidino compounds using specimens collected in February 1989 and in April 1989, and compared for those contents with each other. As for the amount of EN, no remarkable difference was found between two- and three-year-old samples collected at St. 1 in the spring and winter seasons, while at St. 2 in the spring season the two-year-old sample was distinctly lower than the three-year-old one. Taurine, proline, glutamic acid, glycine and alanine were the major FAA in every sample. The amount of taurine, the most prominent FAA, was higher in three-year-old sample than in two-year-old one regardless of sampling station and season. Most of the other major FAA showed a similar tendency to EN at both sampling stations in both seasons. Adenosine 5'-triphosphate (ATP), adenosine 5'-diphosphate (ADP), adenosine 5'-monophosphate (AMP), inosine 5'-monophosphate (IMP), inosine (Ino) and hypoxanthine (Hyp) were detected in all the samples and ATP, ADP and AMP were the major ingredients. The amounts of total NRC were in parallel with those of EN and total FAA. As for the contents of betaines, two- and three-year-old samples collected in the winter season exhibited a great discrepancy each other, the former being clearly lower than the latter, but no remarkable difference was observed between two samples of two groups in the spring season. In proximate composition of the muscles, the two-year-old sample was considerably higher in moisture content and lower in protein and glycogen contents than the three-year-old one at St. 2 in the spring season. The large discrepancies observed between two- and three-year-old samples from St. 2 seems to be attributable to the difference in size of samples rather than to the difference in age.

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Changes in Endogenous Substances in Relation to Stratification of Dormant Taxus cuspidata Seeds (층적처리(層積處理)에 의한 주목종자(朱木種子)의 함유성분(含有成分)의 변화(變化))

  • Wi, Heub;Koh, Dae Shik;Han, Cheol Soo
    • Journal of Korean Society of Forest Science
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    • v.28 no.1
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    • pp.21-30
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    • 1975
  • The purpose of this paper is to elucidate physiologically the cause of the hastening germination of dormant Taxus cuspidata seeds by stratification. During the stratification the exchange of chemical substances such as sugar, protein, starch and fat were observed, and growth promoting and inhibiting substances were extracted and seperated from seeds by the conventional chromatographic method with coleoptile straight-growth test. An intensive investigation was made on the balance between the promoters and inhibitors. consequently, it was confirmed that germination of seeds was accelerated with exchange of chemical substances by stratification. The results obtained may be summarized as follows: 1. During the stratification growth promoters were increased and growth inhibitors were decreased rapidly in the endosperm of seeds. Thus, it was presumed that hastening germination was controlled by balace between the promoters and inhibitors from November to next March after a year's stratification. On the other hand growth promoters were almost constant and growth inhibitors were decreased rapidly in the seed coats, and it was presumed that hastening germination was influenced by exchange of inhibitors more than by that of promoters. 2. As a results of germination test of lettuce seeds, it was generalized that hastening germination was controlled by a decreased amount of growth inhibitors more than by an increased amount of promoters. 3. During the stratification sugar and crude protein contents were increased gradully with moisture content, while starch and crude fat were decreased in endosperm of seeds. So it was assumed that the exchange of these chemical substances was closely related to the germination of seeds.

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Effect of Fermented Herbal Mixture against Oxidative Stress in HepG2 and PC12 Cells (HepG2 및 PC12 세포에서 혼합 한약재 발효물의 산화적 스트레스 억제 활성 평가)

  • Lee, Yunjeong;Kim, Nan-Seul;Shon, Myung-Soo;Kim, Gyo-Nam;Hwang, Yong-Il;Park, Eunju
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.7
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    • pp.1057-1064
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    • 2016
  • This study was carried out to investigate the effect of fermented herbal mixtures (FHMs) in HepG2 and PC12 cells. Two different types of fermented herbal mixtures consisted of Chrysanthemum morifolium, Ganoderma lucidum, Acanthopanax senticosus, Schisandra chinensis, Hovenia dulcis thumb, and Lycii fructus. FHM-A and FHM-B were separately fermented with Prunellae Spica, Portulaca oleracea (FHM-A) and Acorus gramineus, Pycnostelma paniculatum (FHM-B). Total phenolic content of FHM-B was higher than that of FHM-A. ORAC values in both FHM-A and FHM-B increased in a dose-dependent manner, and antioxidant activities against peroxyl radicals were higher in FHM-A than FHM-B. Both FHM-A and FHM-B effectively ameliorated AAPH- and ethanol-induced oxidative stress in HepG2 cells. They also suppressed lipid formation induced by ethanol treatment. In addition, FHM-A and FHM-B prevented $H_2O_2$-induced PC12 cell death. FHM-B showed a relatively stronger protective effect than that of FMB-A. Taken together, these findings show that a fermented herbal mixture could be used in healthy and functional food design for oxidative stress-related diseases.

Analysis of Test Items of Earth Science and the Applicants' Responses on the Items in the College Scholastic Ability Test (대학수학능력시험의 지구과학영역 문항 및 응시자 반응 분석)

  • Lee, Yang-Rak
    • Journal of the Korean earth science society
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    • v.22 no.6
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    • pp.469-479
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    • 2001
  • This study investigated the trends in the number of applicants and mean score and applicants’ responses on the test items of Earth Science in the College Scholastic Ability Test (CSAT) implemented for 3 years (1999-2001). The percentage of applicants of science track were 43.14% in 1995, but reduced through 29.5% in 2001 to 26.92% in 2002 CSAT For elective subject, about 22% of science track students applied to Earth Science II which ranked third to Biology II and Chemistry II. In 1999, test items were developed to have the expected difficulty 40 ${\sim}$ 59% (6 items) to 60 ${\sim}$ 79% (10 items). But in 2001 every 16 items were developed to have difficulty 60 ${\sim}$ 79%, which was caused by the policy of so called ‘easy CSAT’. Thus the mean score of ‘Earth Science II’ was increased from 50.26 in 1999 through 64.47 in 2000, to 67.58 in 2001. Applicants were generally very good at solving test items focusing on process skills only and familar items but poor at solving test items related to the motion of the earth and planets and sea wave, especially items calling two or more concepts. Thus special measures to cope with the decrease in applicants of science track should be provided. And it is recommended to develop test items with wider range of difficulty and to reduce test items calling process skills only. And special consideration should be given to teaching the content area with poor achievement and high actual difficulty compared to the expected.

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The Effects of Science Question Enhancement Instruction on the Science Question Level and Achievement of Middle School Students (질문 강화 수업이 중학생들의 질문 수준과 학업 성취도에 미치는 영향)

  • Chung, Young-Lan;Bae, Jae-Hee
    • Journal of The Korean Association For Science Education
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    • v.22 no.4
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    • pp.872-881
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    • 2002
  • Student questioning is included in the priority of science literacy, to enable students to solve problems by exploring questions, communicating and constructing knowledge(AAAS, 1989). Also, the essence of student questioning in science lies in its function as a link between thinking and learning. But educators did not pay much attention to students' questioning in Korea. The purpose of this study was to investigate the effects of science question enhancement instruction on students' science questioning level and achievement. Also, this study showed the effects of other variables(logical thinking, science achievement, interest, and gender) on students' science questioning level. The pretest-posttest control group design group design was used. The sample was consisted of 80 second grade middle school students in experimental group(Science question enhancement instruction) and 74 students in control group(Traditional learning). Students in both groups were received identical content instruction on the unit 'Structures and functions of plant'. These groups were treated for 15 hours during 6 weeks. Students' questions were rated using the four levels described by the Middle School Students' Science Question Rating Scale(r= .96,)(Cuccio-Schirripa & Steinner, 2000). Science achievement data were collected using a 17 item multiple choice test(Cronbach ${\alpha}$= .84). To investigate students' logical thinking ability, a abridged GALT(Cronbach ${\alpha}$= .69) was used. Five-way ANOVA, ANCOVA, and multiple regression analysis were used to analyze the results. The results indicated that students who received instruction on researchable questioning outperformed those students who were not instructed on high-order questioning(p< .01). Results of correlations indicated that instruction(r= .640), science achievement(r= .311) and logical thinking ability(r= .212) was significantly and positively related with students' questioning level. But, interest and gender did not show any significant correlation with students' questioning level. Science question enhancement instruction was more effective on science achievement than the traditional instruction(p< .01).

Some New Problems of International Aviation Security- Considerations Forcused on its Legal Aspects (최근국제항공보안대책(最近國際航空保安対策)의 제간제(諸間題) -특히 법적측면(法的測面)을 중심(中心)으로-)

  • Choi, Wan-Sik
    • The Korean Journal of Air & Space Law and Policy
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    • v.5
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    • pp.53-75
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    • 1993
  • This article is concerned with the comment on "Some New Problems of International Aviation Security-Considerations Forcused on its Legal Aspects". Ever since 1970, in addition to the problem of failure to accept the Tokyo, Hague and Montreal Conventions, there has been also the problem of parties to them, failing to comply with their obligations under the respective treaties, in the form especially of nominal penalties or the lack of any effort to prosecute after blank refusals to extradite. There have also been cases of prolonged detention of aircraft, passengers and hostages. In this regard, all three conventions contain identical clauses which submit disputes between two or more contracting States concerning the interpretation or application of the respective conventions to arbitration or failing agreement on the organization of the arbitration, to the International Court of Justice. To the extent to which contracting States have not contracted out of this undertaking, as I fear they are expressly allowed to do, this promision can be used by contracting States to ensure compliance. But to date, this avenue does not appear to have been used. From this point of view, it may be worth mentioning that there appears to be an alarming trend towards the view that the defeat of terrorism is such an overriding imperative that all means of doing so become, in international law, automatically lawful. In addition, in as far as aviation security is concerned, as in fact it has long been suggested, what is required is the "application of the strictest security measures by all concerned."In this regard, mention should be made of Annex 17 to the Chicago Convention on Security-Safeguarding International Civil Aviation against Acts of Unlawful Intereference. ICAO has, moreover, compiled, for restricted distribution, a Security Manual for Safeguarding Civil Aviation Against Acts of Unlawful Interference, which is highly useful. In this regard, it may well be argued that, unless States members of ICAO notify the ICAO Council of their inability to comply with opecific standards in Annex 17 or any of the related Annexes in accordance with Article 38 of the 1944 Chicago Convention on International Civil Aviation, their failure to do so can involve State responsibility and, if damage were to insure, their liability. The same applies to breaches of any other treaty obligation. I hope to demonstrate that although modes of international violence may change, their underlying characteristics remain broadly similar, necessitating not simply the adoption of an adequate body of domestic legislation, firm in its content and fairly administered, but also an international network of communication, of cooperation and of coordination of policies. Afurther legal instrument is now being developed by the Legal Committee of ICAO with respect to unlawful acts at International airports. These instruments, however, are not very effective, because of the absence of universal acceptance and the deficiency I have already pointed out. Therefore, States, airports and international airlines have to concentrate on prevention. If the development of policies is important at the international level, it is equally important in the domestic setting. For example, the recent experiences of France have prompted many changes in the State's legislation and in its policies towards terrorism, with higher penalties for terrorist offences and incentives which encourage accused terrorists to pass informations to the authorities. And our government has to tighten furthermore security measures. Particularly, in the case an unarmed hijacker who boards having no instrument in his possession with which to promote the hoax, a plaintiff-passenger would be hard-pressed to show that the airline was negligent in screening the hijacker prior to boarding. In light of the airline's duty to exercise a high degree of care to provide for the safety of all the passengers on board, an acquiescence to a hijacker's demands on the part of the air carrier could constitute a breach of duty only when it is clearly shown that the carrier's employees knew or plainly should have known that the hijacker was unarmed. The general opinion is that the legal oystem could be sufficient, provided that the political will is there to use and apply it effectively. All agreed that the main responsibility for security has to be borne by the governments. A state that supports aviation terrorism is responsible for violation of International Aviation Law. Generally speaking, terrorism is a violation of international law. It violates the sovereign rights of states, and the human rights of the individuals. We have to contribute more to the creation of a general consensus amongst all states about the need to combat the threat of aviation terrorism. I think that aviation terrorism as becoming an ever more serious issue, has to be solved by internationally agreed and closely co - ordinated measures.

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Apoptotic Effect of co-treatment with HS-1200 and Cisplatin on SCC25 Human Tongue Squamous Cell Carcinoma Cell Line (HS-1200과 cisplatin의 병용처리가 사람구강암세포에 미치는 세포자멸사 효과에 대한 연구)

  • Kim, Duk-Han;Kim, In-Ryoung;Park, Bong-Soo;Ahn, Yong-Woo;Jeong, Sung-Hee
    • Journal of Oral Medicine and Pain
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    • v.38 no.3
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    • pp.221-233
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    • 2013
  • Bile acids are polar derivatives of cholesterol essential for the absorption of dietary lipids and regulate the transcription of genes that control cholesterol homeostasis. Recently it have been identified the synthetic chenodeoxycholic acid (CDCA) derivatives HS-1200 and cisplatin showed apoptisis-inducing activity on various cancer cells in vivo and in vitro. This study was undertaken to investigate the synergistic apoptotic effect of co-treatment with HS-1200 and cisplatin on human tongue squamous cell carcinoma cells (SCC25 cells). To investigate whether the co-treatment with HS-1200 and cisplatin compared to each single treatment efficiently reduces the viability of SCC25 cells, MTT assay was conducted. The induction and augmentation of apoptosis were confirmed by DNA electrophoresis, Hoechst staining and an analysis DNA hypoploidy. Westen blot analysis and immunofluorescent staining were also performed to evaluate the expression levels and the translocation of apoptosis-related proteins following this co-treatment. Furthermore, proteasome activity and mitochondrial membrane potential (MMP) change were also assayed. In this study, co-treatment with HS-1200 and cisplatin on SCC25 cells showed several lines of apoptotic manifestation such as nuclear condensations, DNA fragmentation, reduction of MMP and proteasome activity, the increase of Bax and the decrease of Bcl-2, decrease of DNA content, the release of cytochrome c into cytosol, translocation of AIF and DFF40 (CAD) onto nuclei, and activation of caspase-9, caspase-7, caspase-3, PARP and DFF45 (ICAD) whereas each single treated SCC25 cells did not show these patterns. Although the single treatment of $25{\mu}M$ HS-1200 and $4{\mu}g/ml$ cisplatin for 24 h did not induce apoptosis, the co-treatment of these reagents prominently induced apoptosis. Therefore our data provide the possibility that the combination therapy with HS-1200 and cisplatin could be considered as a novel therapeutic strategy for human squamous cell carcinoma.

Development and Validation of Inventory of the Anger-inducing Automatic Thoughts for Elementary School Children (아동용 분노유발 자동적 사고 검사의 개발과 타당화)

  • Kim, Seon-Hwa;Park, Gyoung-Mook
    • The Korean Journal of Elementary Counseling
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    • v.9 no.1
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    • pp.41-58
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    • 2010
  • The purpose of this study was to invent anger-inducing automatic thoughts examination for elementary school children based on its investigation for Korean one. I made the anger-inducing Automatic Thoughts Questionnaire(I, II) and made an examination of the contents of the automatic thoughts with it. Based on it, with preliminary questionnaire 90, I did principal component analysis varimax rotation and then final anger-inducting automatic thoughts examination of 40 question in 2 primary factor construction was consisted. I made 300 students carry out it to know its reliability, propriety and made 100 students carry it out at 2-week intervals test-retest. I divided them in three groups as low, middle and high according to its soore regarding anger-inducting automatic thoughts, I confirmed the variation of each group in positive thoughts, self-esteem, life satisfaction, anger, the result is same as follows; First, the content of Anger-inducting Automatic thoughts for elementary school students is revealed as unreasonableness(56.4%), retailation and passive, active offense(16.3%), blame and contempt(11.9%), injured pride and refusal(9.2%), absurd(3.9%), abandonment and avoidance(2.1%), self-abasement in turn. Second, said inventory is consist of 2 notion; first(20 questions) is blame, retaliation and second(20 questions) is injustice. Inner-item consistency of total 40 question is .97, Split-half reliability is .93, Test-retest reliability is .86. Third, criterion validity is revealed fine by reviewing the correlation between existing index related to the inventory of Anger-inducting Automatic thoughts of the elementary school students. Moreover, to find out discriminant validity, I divided three classes(low, middle, high) according to the score of said thoughts. As a result, there is certain variations when I confirmed variations in groups by reviewing the self-esteem, positive way of thinking, life satisfaction, anger.

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Characterization of Salt Tolerant Rice Mutant Lines Derived from Azetidine-2-Carboxylic Acid Resistant Cell Lines Induced by Gamma Ray Irradiation (AZCA 저항성 돌연변이 세포주로부터 선발 육성만 내염성 벼 돌연변이 계통의 특성 검정)

  • Song, Jae-Young;Kim, Dong-Sub;Lee, Geung-Joo;Lee, In-Sok;Kang, Kwon-Kyoo;Yun, Song-Joong;Kang, Si-Yong
    • Journal of Plant Biotechnology
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    • v.34 no.1
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    • pp.61-68
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    • 2007
  • To develop rice (Oryza sativa L.) cultivars to be planted on salt-affected sites, cell lines with enhanced proline content and resistance to growth inhibition by Azetidine-2-carboxylic acid (AZCA), a proline analogue, were screened out among calli irradiated with gamma ray of 50, 70, 90, and 120 Gy. The calli had been derived from embryo culture of the cultivar Donganbyeo. Selected AZCA resistant lines that had high proline accumulation were used as sources for selection of NaCl resistant lines. To determine an optimum concentration for selection of NaCl resistant lines, Donganbyeo seeds were initially cultured on the media containing various NaCl concentrations (0 to 2.5%) for 40 days, and 1.5% NaCl concentration was determined as the optimum concentration. One hundred sixteen salt-tolerant (ST) lines were selected from bulked 20,000 seeds of the AZCA resistant $M_{3}$ seeds in the medium containing 1.5% NaCl. The putative 33 lines ($M_{4}$ generation) considered with salt-tolerance were further analyzed for salt tolerance, amino acid and ion contents, and expression patterns of the salt tolerance-related genes. Out of the 33 lines, 7 lines were confirmed to have superior salt tolerance. Based on growth comparison of the entries, the selected mutant lines exhibited greater shoot length with average 1.5 times, root length with 1.3 times, root numbers with 1.1 times, and fresh weight with 1.5 times than control. Proline contents were increased maximum 20%, 100% and 20% in the leaf, seed and callus, respectively, of the selected lines. Compared to control, amino acid contents of the mutants were 24 to 29%, 49 to 143%, 32 to 60% higher in the leaf, seed and callus, respectively. The ratio of $Na^{+}/K^{+}$ for most of the ST-lines were lower than that of control, ranging from 1.0 to 3.8 for the leaf and 11.5 to 28.5 for the root, while the control had 3.5 and 32.9 in the leaf and root, respectively. The transcription patterns for the P5CS and NHXI genes observed by RT-PCR analysis indicated that these genes were actively expressed under salt stress. The selected mutants will be useful for the development of rice cultivar resistant to salt stress.